The present invention relates to a clamp, and more particularly to a clamp for clamping screwed fastening members such as self-tightening screws.
In a DIY product, self-tightening screws are often used to lock a work piece. In operation, a screwdriver is used to press a self-tightening screw against the work piece and screw the self-tightening screw into the work piece. The work piece is not drilled with any hole so that the self-tightening screw is purely forcedly screwed into the work piece by the strength of the operator. Therefore, the self-tightening screw has a sharp front tip for nailing into the work piece. Prior to screwing into the work piece, in the case that the force exerted by the operator onto the self-tightening screw is not normally aligned with the self-tightening screw and an oblique component force exists, it often takes place that the self-tightening screw is deflected and dropped or even irregularly bounded out to injure the operator.
In order to solve this problem, a clamp has been developed, which is mounted on the screwdriver for clamping the self-tightening screw. When screwing the screw with a screwdriver, the self-tightening screw can be fixed without deflection, dropping or randomly bounding.
However, the conventional clamp has quite complicated structure and is difficult to manufacture. Therefore, the cost for such clamp is high. Moreover, there are various kinds of self-tightening screws on market and the conventional clamp is only applicable to some of these self-tightening screws.